gRPC protoc GO Client

Go protoc generated GrpcServiceClient TodoWorld Example​

Install x dotnet tool:

$ dotnet tool install --global x 

Create new TodoWorld Go module:

$ go mod init TodoWorld

Add protoc generated TodoWorld DTOs and gRPC GrpcServiceClient to services/ folder:

$ mkdir services
$ x proto-go https://todoworld.servicestack.net -out services

Go protoc gRPC insecure Example​

Create a new Go Console App in client\main.go:

package main

import (
    context "context"
    "fmt"
    "log"

    "google.golang.org/grpc"

    pb "TodoWorld/services"
    "time"
)

func main() {
    conn, err := grpc.Dial("todoworld.servicestack.net:5054", grpc.WithInsecure())
    if err != nil {
        log.Fatalf("fail to dial: %v", err)
    }
    defer conn.Close()

    client := pb.NewGrpcServicesClient(conn)
    ctx, cancel := context.WithTimeout(context.Background(), time.Second)
    defer cancel()

    response, err := client.GetHello(ctx, &pb.Hello{Name: "gRPC Go"})
    if err != nil {
        log.Fatalf("GetHello: %v", err)
    }
    fmt.Println(response.Result)
}

Alternatively above Go example can be created with:

$ mkdir client
$ x mix todoworld-go -out client

Run example:

$ go run client\main.go

Go protoc gRPC SSL Example​

Download TodoWorld SSL Certificate used for its gRPC HTTP/2 Services:

$ x get https://todoworld.servicestack.net/grpc.crt 

Use certificate when initializing NewGrpcServicesClient:

package main

import (
    context "context"
    "fmt"
    "log"

    "google.golang.org/grpc"
    "google.golang.org/grpc/credentials"

    pb "TodoWorld/services"
    "time"
)

func main() {
    creds, err := credentials.NewClientTLSFromFile("grpc.crt", "")
    if err != nil {
        log.Fatalf("could not process the credentials: %v", err)
    }

    conn, err := grpc.Dial("todoworld.servicestack.net:50051", grpc.WithTransportCredentials(creds))
    if err != nil {
        log.Fatalf("fail to dial: %v", err)
    }
    defer conn.Close()

    client := pb.NewGrpcServicesClient(conn)
    ctx, cancel := context.WithTimeout(context.Background(), time.Second)
    defer cancel()

    response, err := client.GetHello(ctx, &pb.Hello{Name: "gRPC Go"})
    if err != nil {
        log.Fatalf("GetHello: %v", err)
    }
    fmt.Println(response.Result)
}

Override client/main.go with the above Go Example:

$ x mix todoworld-go-ssl -out client

Run example:

$ go run client\main.go

Go Local Development gRPC SSL CRUD Example​

package main

import (
    context "context"
    "fmt"
    "log"

    "google.golang.org/grpc"
    "google.golang.org/grpc/credentials"

    "time"
    pb "todoworld/services"
)

func main() {

    // Load the certificates from disk
    creds, err := credentials.NewClientTLSFromFile("dev.crt", "localhost:5001")
    if err != nil {
        log.Fatalf("could not process the credentials: %v", err)
    }

    conn, err := grpc.Dial(address, grpc.WithTransportCredentials(creds))
    if err != nil {
        log.Fatalf("fail to dial: %v", err)
    }
    defer conn.Close()

    client := pb.NewGrpcServicesClient(conn)
    ctx, cancel := context.WithTimeout(context.Background(), time.Second)
    defer cancel()


    _, err = client.PostResetTodos(ctx, &pb.ResetTodos{})
    if err != nil {
        log.Fatalf("PostResetTodos: %v", err)
    }

    fmt.Println("TODO EXAMPLE")

    //POST /todos
    r1, err := client.PostCreateTodo(ctx, &pb.CreateTodo{Title: "ServiceStack"})
    if err != nil {
        log.Fatalf("PostCreateTodo: %v", err)
    }
    todo := r1.Result
    fmt.Println("new todo Id:", todo.Id, "Title:", todo.Title)

    //GET /todos
    all, err := client.CallGetTodos(ctx, &pb.GetTodos{})
    if err != nil {
        log.Fatalf("CallGetTodos: %v", err)
    }
    fmt.Println("todos:", len(all.GetResults()))

    //GET /todos/1
    r2, err := client.CallGetTodo(ctx, &pb.GetTodo{Id: todo.Id})
    if err != nil {
        log.Fatalf("CallGetTodo: %v", err)
    }
    todo = r2.Result
    fmt.Println("get todo Id:", todo.Id, "Title:", todo.Title)

    //PUT /todos/1
    _, err = client.PutUpdateTodo(ctx, &pb.UpdateTodo{Id: todo.Id, Title: "gRPC"})
    if err != nil {
        log.Fatalf("PutUpdateTodo: %v", err)
    }

    //GET /todos/1
    r2, err = client.CallGetTodo(ctx, &pb.GetTodo{Id: todo.Id})
    if err != nil {
        log.Fatalf("CallGetTodo: %v", err)
    }
    todo = r2.Result
    fmt.Println("get todo Id:", todo.Id, "Title:", todo.Title)

    //DELETE /todos/1
    _, err = client.CallDeleteTodo(ctx, &pb.DeleteTodo{Id: todo.Id})
    if err != nil {
        log.Fatalf("CallDeleteTodo: %v", err)
    }

    //GET /todos
    all, err = client.CallGetTodos(ctx, &pb.GetTodos{})
    if err != nil {
        log.Fatalf("CallGetTodos: %v", err)
    }
    fmt.Println("todos:", len(all.GetResults()))
}

Refer to /clients/go for a complete example project.